This proposal seeks support for the 19th Bacterial Cell Surfaces Gordon Conference, which will be held from June 27 to July 2, 2010 at Colby-Sawyer College in New London, New Hampshire. The meeting focuses on the biogenesis, structure and function of bacterial envelopes and surfaces, including bacterial membranes, cell walls, and surface appendages and polymers. This conference presents a diverse program in topics, model systems, and approaches combining biochemistry, molecular genetics, structural biology, biophysics, imaging and modeling. There will be 9 sessions on topics related to 1) peptidoglycan cell walls, 2) outer membranes, 3) signal sensing and transduction, 4) cell morphogenesis, 5) cell envelope stress and periplasm, 6) protein localization and secretion, 7) microbial communities and antibiotics, 8) transport, and 9) extracellular organelles and surface structures. The objectives of this conference are to: 1) present the latest and most exciting research in these areas by bringing together a diverse group of scientists with respect to approaches, expertise, experimental model, and seniority;2) generate new ideas and stimulate intellectual exchange between this diverse group of investigators;and 3) provide opportunities for graduate students and postdoctoral fellows to present their work in short-talk or poster format and to interact with leaders in the field. The traditional format of the Gordon Research Conferences, with programmed discussion sessions and opportunities for informal gatherings in the afternoons and evenings, conveys a collegial atmosphere where interactions between attendees are easily attained. Although the science presented is basic in nature, the topics of this multi- faceted conference are of practical interest to the biomedical community in the areas of pathogenesis, antibiotic action and resistance, and host-microbe interactions, as many of these phenomena involve processes at the level of membranes, cell walls and cell surface. This conference will thus provide a platform for future developments of vaccine and antibacterial strategies. The overall theme of the conference is the structure, function and biogenesis of the bacterial cell envelope and surface, which are intimately associated with bacterial pathogenesis as well as resistance to major antibacterial agents. This conference will bring prominent and junior scientists together to present their latest research and to spur collaboration and exchange of ideas and knowledge in a conducive environment.